The synergistic adsorption of hydrophobic anion and a polyvalent meta cation to phospholipid membrane (PE), has been studied extensively using tetraphenylborate (TPB^-) and Th⁴⁺ as the respective ions, It is realized that the synergistic adsorption of these ions has proceeded in a step wise manner and in the low concentration region of these ions, the behaviour is controlled mainly by the binding of Th⁴⁺ to phospholipid (PE) vesicles, which are negatively charged under the present experimental conditions. With increasing the concentrations, the adsorption amount of TPB^- is enhanced extensively and the binding molar ratio of TPB^- to Th⁴⁺ approached to the value expected from the electrical neutrality, i. e., TPB^-/Th⁴⁺=4. Such a behaviour is also realized by measuring the surface potential of the monolayer, which shows excess negative values under the high TPB^- concentrations.

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The viscosity of octadecyltrimethylammonium chloride (OTAC) aqueous solution containing 1-hexadecanol (C₁₆OH) was influenced by the molar ratio of C₁₆OH/OTAC and the preparation temperature. In the region of the molar ratio below 1.5, the solution was not viscous, but the viscosity of the solution in the region of molar ratio above 1.5 was changed markedly by the difference in preparation temperature. High viscous solution was obtained at 55°C, but the low viscous solution was obtained at 77°C. The electrical conductivity and melting point of the solution also changed at the molar ratio 1.5. Below 1.5, the conductivity lowered with an increase in the molar ratio, but it was constant in the region above 1.5. There were two types of complexe s G₁ and G₂ in the ternary system. The complex G₁ with low melting point was observed only at the molar ratio below 1.5. On the other hand, in the region above 1.5, the melting point of the complex G₂ raised with an increase in the molar ratio and became constant above 3.O.

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Properties of silica gel surfaces, calcined at the temperature higher than 973 K, were studied by IR spectroscopy, butylamine titration method, propylene oxide isomerization reaction, and ESCA. Pyridine-adsorbed sample, previously calcined at 1173K for 2h in air, showed two infrared absorption bands at.1446 and 1598 cm^-1. These bands did not disappear even after evacuation of the sample at 673 K for 0.5 h. The sample possessed an acidity of 0.041 mmol.g^-1 at H_o<+3.3 and no basicity with H_>+7.2. No peak due to chemisorbed carbon dioxide was detected in IR spectra. Propylene oxide was found to isomerize to propionaldehyde, allyl alcohol, acetone, acrylaldehyde and 1- and 2- propanols. The formation of allyl alcohol, acrylaldehyde and propanols requires the presence of basic active sites. These results suggest the existence of Lewis acid sites and base sites, of which strength may be weak. Number of Al atom on the silica-gel surface calcined at 773K was estimated to be 1.0×10¹³ atom.cm^-2 by an ESCA technique, which agreed with the acid density of 9.4×10¹² site.cm^-2with H_o<+3.3. Accordingly it is concluded that the strong Lewis acid sites are formed on Al atoms. ESCA measurement indicated an existence of Na atoms, which would contribute to an occurrence of base sites. Specific isomerization reaction rates of propylene oxide to propionaldehyde, allylf alcohol, and acetone increased with the elevation of calcination temperature. And surface area, acidity, and integrated absorbance at 1446 cm^-1 due to the adsorbed pyridine in IR spectra gradually decreased. On the basis of these data and pyridine-poisoning effects, were discussed relationships between the rate of isomerization reaction and the strength of Lewis acid site,

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Metal-supported Y-type zeolites were prepared under several, conditions, and their catalytic activities for cumene cracking and toluene disproportionation reactions were investigated to reveal unique properties of Fe-supported systems. In a pulse reactor under an atmospheric pressure, Cu, Ni, and Co-supported zeolites increased their catalytic activities when treated with H₂, and especially with FI, H₂S(Figs.2, 4, 6, 7). The activity increases were interpreted as resulting from the reduction of the supported metal ions coupled with the formation of Brφnsted acid sites. On the other hand, Fe-supported zeolites hardly increased their cumene cracking activities by the treatments with H₂S and H₂(Fig.5), while they were found to be effective. for the toluene disproportionation activities (Fig. 7), by the treatment with H₂S. Experiments using a high-pressure bed reactor fixed with catalyst showed that under the presence of H₂S was achieved the highest activity for toluene disproportionation with a Fesupported zeolite (FeHY-1), on which Fe species were supported under such conditions that the zeolite framework underwent partial dealumination (Fig.8). Futhermore, it was found that the disproportionation activity of FeHY-1 was promoted with H₂S only when H₂S was present in the reaction atmosphere, its stationary activity being dependent on the concentration of H₂S (Figs.12, 13).

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The stability of acid sites in the zeolites containing Ca, which are effective in the production of light olefins from methanol, was studied. The increase in the catalytic activity was observed after the conversion of methanol at 600°C (Fig.1). In order to clarify the reason, the zeolites before and after conversion of methanol were characterized by FT-IR, K+ ion exchange, and XPS. In FT-IR spectrum of the zeolite after the reaction, remarkable increase in the peak intensity at 3605 cm-1 assigned to the Brφnsted strong acid sites was observed. On the other hand, the peak intensity at 3660 cm-1 assigned to the weak acid sites, formed by modification with Ca, decreased (Fig.2). XPS data showed the increase in Ca/Si ratio at the zeolite external surface (Table 1). These results indicate that the increase in the amount of strong acid sites is attributed to the release of a part of Ca from the weak acid sites and that a part of Ca migrate to the zeolite external surface. Next, the influence of reaction temperature, reaction time, and steam treatment on the release of Ca from the weak acid sites was studied. The pronounced release of Ca was observed during the conversion of methanol above 550°C (Fig.3). The catalytic activity increased with the reaction time at 600°C and reached constant after about 7 h (Fig.4). The increase in the catalytic activity was not promoted by heat treatment but by steam treatment (Fig.5). These results demonstrate the release of Ca during the reaction is attributed to the effect of steaming. Thus, the increase in the amount of strong acid sites by the release of Ca from the weak acid sites seems to promote the formation of B. T. X and the coke deposition which is responsible for deactivation of the zeolites.

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Mossbauer spectroscopy (MES) and transmission electron microscopy (TEM) were applied to study Fe supported Y-type zeolite (FeHY-1) which was prepared by treating NH₄Y zeolite with iron(III) nitrate solution. TEM measurements revealed that the particle size of Fe species was less than 10A (Fig.1), while MES measurements at room tetriperatureindicated the presence of octahedrally coordinated, trivalent Fe cations (Table 2). The MES spectra recorded at 4.2 K consisted of a broad signal with six lines hyperfine structure (H_lnt=46.0T), and a relatively intense quadrupole doublet (IS=0.49 mm.s^-1, QS=1.10 mm.^-1) (Fig.5), indicating the presence of two types of iron(III) oxides species. It was interpreted that the Zeeman splitting was ascribed to the super fine particles of iron(III)oxide formed in the super cage of zeolite, whereas the quadrupole doublet was ascribed to the iron(III) oxide bonded to zeolite framework.

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A new artificial superlattice composed of PbSe and SnSe, (PbSe)_m(SnSe)_n, was characterized by the X-ray diffraction method and the cross-sectional transmission electron microscopy. The two materials in their bulk forms possess different crystal structures. PbSe has the cubic NaCl-type structure, whereas SnSe has the orthorhombic SnS-type structure (Fig.1). It was found from the evaluation of X-ray intensity of the satellite peaks that the samples have an ideal superstructure whose compositional modulation can be described by the step model (Figs.3, 4). In addition, the samples adopt one of four types of lattice structures depending on m and n (Fig.8). In particular, when they are designed as n>(2/3)m and m<6, a single crystal artificial superlattice with SnS-type structure can be obtained, wh ile for n<(2/3)m and n<4, NaCl-type is found. This is because the pseudomorphic structure formed at the beginning of the thin film growth on a lattice-mismatched substrate can be retained in the superlattice structure if the layer thicknesses are controlled precisely below the critical values which are 1.8 nm for PbSe and 1.2 nm for SnSe.

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A chromia-silica catalyst has been developed for the catalytic oxidation of HCl to Cl₂. The catalyst yield high HCl conversions of 70-75% at 380°C and has a space velocity of 400Nl HCl/h.kg. The insensitivity of the catalyst to poisons was substantiated by the successf ul use of by-produced HCl containing 2-4% CO and organic impurities. The decrease of catalytic activity was within permissible limits for up to about 900 h (Table 3). Preliminary evaluation of a number of catalysts, including CuCl₂-KCl-CeCl₃/SiO₂, showed that the chromia catalyst yielded better results than did the conventional Deacon type catalyst, which is the best available for the reaction (Table 1).
On the chromia catalyst, the reaction proceeds through oxidation reduction mechanism of catalyst and does not proceed through oxide-chloride cycle. Activity of the catalyst is due to the capability of retaining excess oxygen on chromia. The amount of excess oxygen, estimated from reduction of the chromia catalyst with HCl or exchange of ¹⁸O between the chromia catalyst and CO₂, is 6-7×10^-4 g.atom/g.cat (Fig.1). The rate of the reaction found from measurement in an integral reactor is represented by the equation r=k_pP_O3^0.5P_HCl². The activation energy of the reaction was 45 kcal/mol (Figs.2, 3, 4 & Table 4, 5). The rate determining step of the reaction is the reaction of excess oxygen on chromia with HCl.

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Trace elements dissolved in the Tama river were analyzed by an instrumental neutron activation analysis (INAA). River water samples were taken from 15 points of the Tama river, which runs through the Metropolis of Tokyo, about 6 times from 1980 to 1983. The water samples were activated for two methods, a solution activation method a n d a freeze-dried activation method. In the solution method, 30-50 ml samples in polyethylene bottles were irradiated at an irradiation pit (7.5×10¹¹ n.cm^-2.s^-1) in the Musashi Institute of Technology Research Reactor (MITRR). In the freeze dried method, 150-400 ml samples were frozen-dried at 40°C, and the dry residues were irradiated in a pneumatic transfer system (1.5×10¹² n.cm^-2.s^-1) or a central thimble (3.2×10¹² n.cm^-2 s^-1). Gamma-ray spectra for the irradiated samples were measured by a Ge(Li) detector coupled with a multichannel analyzer and a minicomputer (GAMA system). Twenty-five elements (Mg, Mn, Cl, Na, V, Al, Ca, Sm, Br, As, K, Cr, Sb, Sc, Fe, Co, Cs, Zn, Th, Sr, Rb, Se, Ag, Ba, Ni) were analyzed by these methods. As a result, we found that the concentrations of analytical elements at each sampling point were nearly constant independently of weathers and seasons. The concentration of most of these elements increased from the upper reaches through the middle reaches to the lower reaches, especially further increased from Hamura intake dam to the lower reaches. The elements dissolved in the Tama river were divided into two groups. The concentrations of Br, Ni, Mn, Fe, Co, Cl, K and Na changed greatly from upper reaches to lower reaches. The concentrations of Ca, As, Sb, Sr, Al, Mg, V, Ba, Zn and Rb did not change so much from upper reaches to lower reaches. The Br concentration increased from 2 ppb at the upper reaches to 240 ppb at the lower reaches, and the concentration ratio of Cl to Br decreased from 240-900 at the upper reaches to 50-190 at the lower reaches. This result suggests the influence of human activities.

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Four reagent gases, oxygen, methane, isobutane and ammonia, were investigated in chemical ionization mass spectrometry using Townsend discharge (TD). The discharge in oxygen, methane, isobutane and ammonia was initiated at the, ionization chamber pressure of 0.19, O.45, 0.31 and O.38 Torr, respectively. In oxygert, extremely stable discharge was observed at a wide range. Oxygen generated efficiently oxide ions (0⁺, 0^-) and superoxide ions (O₂⁺, O₂^-) in the positive and negative ion mode, respectively. In methane, the sta ble discharge region was dependent on the ionization chamber pressure and discharge voltage, and it was devided into two sections. The composition of the reactant ions was somewhat different from the one of the filament mode, in that the relative ion abundance of C₂H₅⁺ in TD mode was larger than the one of the filament mode, and a small amount of C₄H₇⁺ and C₄H₉⁺ were generated in the TD mode. In isobutane, the stable discharge region was very narrow. The composition of the reactant ions was almost the same as the one of the filament mode. In ammonia, the feature of the stable discharge region was similar to the one in the case of methane. The ion species were the same as those generated in the filament mode, but the relative intensity ratio was different from each other. The repeatabilities of positive and negative ion chemical ionization mass spectra of perfluorotributylamine and decafluorotriphenylphosphine in TD mode using methane reagent gas were almost the same as those of the filament mode. The calibration graph of benzo[α]pyrene in the range of 0-150 pg using benzo[α]pyrene-d₁₂ as an internal standard in methane reagent gas showed good linearity with correlation coefficient of 0.9999.

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On mixing the solutions of selenoamides and iodine in dichloromethane, adducts, RCSeNH₂.nI₂, [1b-e] were formed as precipitates. The adducts [1b-c], derived from p-CH₃OC₆H₄CSeNH₂, and p-(CH₃)₂NC₆H₄CSeNH₂, were heated at their melting points to give 1, 2, 4-diselenazolium compounds [2b, c], respectively. The adduct [1e] from 1-pyrrolidinecarboselenoamide, however, remained intact on heating at melting point. On the other hand, selenobenzamide gave the diselenazolium compound [2a], directly by mixing with iodine solution. The reactions of purified 3, 5-bis(p-dimethylaminophenyl)-1, 2, 4-diselenazolium triiodide with ammonia and hydrazine were examined. As a result, it was found that th e diselenazolium cation behaves in the same manner as the corresponding dithiazolium cation.

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Oxidative lactonization of α, ω-diols with sodium bromite (NaBrO₂) was studied in an alkaline aqueous solution. The oxidation proceeded effectively and stoichiometrically at room temperature in the. presence of a small amount of metal ions such as Cu, Cu²⁺, Ru³⁺, Fe³⁺ or Al³⁺. No oxidation occurred without the metal ions. It is suggested from the UV absorption spectroscopy that copper(II) sulfate reacted with sodium bromite to give unstable copper(II) bromite. Reaction of lactonization is proposed as follows.

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Friedel-Crafts reactions of substituted benzenes with benzenesulfonyl chloride for aluminum chloride in nitrobenzene have been studied kinetically. The rate data obtained in the case of vario us substituted benzenes, suggested the following reaction scheme. The rate constants k₃(=k₁.k₂/k_₁) were in good agreement with Hammett-type linear free energy relationships, Brown-Okamoto's σ⁺ (ρ=-5.3). It was found from the temperature effect on the isomer distribution that in phenylsulfonylation, (m-/p-) ratio of toluene and (o-/p-) ratio of anisole increased with temperature, but (o-/p-) ratio of toluene decreased. Differences in activation energies and activation entropies at the o- and p- positions and the m- and p-positions for toluene and the o- and p-positions for anisole were -0.27 kcal/mol, -O.71 e.u./mol, 0.92, 1.4, and 0.58, 0.33, respectively.

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The effects of surfactant on radiation-induced dechlorination of carbon tetrachloride which occurs via chain mechanism were investigated in aqueous 2-propanol (25 vol%) solutions by using γ-rays as an initiator, and by using surfactants such as sodium 1-dodecanesulfonate, sodium dodecyl sulfate (SDS), hexadecyltrimethylammonium bromide (CTAB), and hexadecyltrimethylammonium chloride (CTAC). The rate of the reaction decrease d by a factor of 1.3-2 in 3-56 mmol.dm^-3 surfactant solutions as shown in Table 1. Based on the kinetic data, the retardation was attributed to the formation of a complex between the surfactant micelle, M, and CCl₃ radical which is a chain carrier in the reaction. The complex formation probably shown by the equation CCl₃+M_??_MCCl₃ gives rise not only to the inhibition of the propagation reaction in the chain but also to the new termination reaction CCl₃+MCCl₃→MC₂Cl₆. The rate constant for the reaction CCl₃+(CH₃)₂CHOH→CHCl₃+(CH₃)₂COH was obtained to be 4.4 mol^-1.dm³.s^-1

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Complexes of chlorotriphenylstannane or isothiocyanatotriphenylstannane with lactams having general formula Ph₃SnX.L (X=Cl, or NCS, L=2-pyrrolidone, 1-methyl-2-pyrrolidone, δ-valerolactam, or ε-caprolactam) in which the carbonyl oxygen in L acted as a donor atom, were examined in solution by IR, ¹¹⁹Sn-NMR, and ¹H-NMR spectroscopies. These complexes, which had a trigonal bipyramidal structure around tin in a s olid state, were found to dissociate in solution and reach equilibrium. The equilibrium constants were determined from the changes of chemical shifts δ(¹H) arising from the ortho-protons of phenyl rings. In solution the isothiocyanato complexes were found to be more inert to the ligand dissociation than the chloro complexes. Chemical shifts of ligand protons were observed at higher field as compared with free lactams. These upfield shifts appear to arise from the shielding effect caused by the aromatic ring.

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An ion sensitive field effect transistor (ISFET) glucose sensor was studied using an immobilized thermophilic enzyme glucokinase from a moderate thermophilic bacterium. The ISFET glucose sensor, on which the glucokinase and albumin were immobilized by glutaraldehyde, was able to determine the glucose concentration in the range of 5-50 mg/dl. The response time of the glucose sensor was about 5 min. The selectivity of the glucose sensor was studied by measuring the responses to various sugars, and the sensor did not respond to other sugars except glucose. Therefore, the glucose sensor was found to have high selectivity for glucose. The sensor also revealed high reproducibility. The coefficient of variation of the sensor was found to be 6.5% for 12 samples containing 20 mg/dl glucose. The storage stability of the sensor was retained for.15 days. However, the output voltage of the sensor decreased to about 50% of the initial output voltage after 20 days. On the other hand, it is obvious that the glucose sensor is al so applicable to, an ATP sensor since the glucokinase catalyzes the reaction between glucose and ATP. Then an ISFET glucose sensor was applied to an ISFET ATP sensor using the immobilized thermophilic glucokinase. The ATP sensor was found to determine the ATP concentration in the range of 50-500 mg/dl.

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Hydroxymethylation of melamine with formaldehyde was kinetically investigated at 40°C in aqueous N-methylmorpholine (pH 7.79-8.72), N, N'-dimethylpiperazine (pH 8.59-9.71), 4-hydroxy-N-methylpiperidine (pH 9.60-10.41), and N-methylpiperidine (pH 10.29-11.70)buffer solutions. As a result, the second order rate constant k was given by Here, k' shows the rate constant in unbuffered media, and HB⁺ and B, the acidic and basic consitituents of the buffers, respectively. On the basis of the Brφnsted plot established by the use of the k_B, values of the above equation, the mechanism of the general base-catalyzed reaction (the third term on the right hand side of the above equation) was discussed in order to determine the rate-determining step in the reaction,

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The degree of dissociation of glycol chitosan (GC) and poly (potassium vinyl sulfate) (PVSK)and their conformation, and the dissociation of hydrated coordination of aluminium chloride hydroxide (PAC) are appreciably influenced by the hydrogen ion concentration. Macromolecular complexes (MC) consisting of GC are stable in acidic and alkaline solutions. On this point of view, the MC were prepared by mixing PVSK with the mixture of PAC and GC at various concentrations of hydrogen ion and in different orders of mixing. The results of IR spectra, elemental analyses, phase diagram in ternary solvent system, and solubility of the MC, indicated that the structure and property of MC varied with the experimental conditions and the content of PAC in MC played an important role in determining the structure of MC. It was sugg ested that the MC obtained at pH 1.0 are products consisting of PVSK, GC, and aluminium aqua complex whereas the MC at pH 4.0 are higher molecular weight products consisting of PVSK, GC, and basic aluminium multidentate complex. The structure however, could not in detail be determined. The MC consisting of PAC, GC, and PVSK was casted into stable and strong membrane in acidic and alkaline solutions from 1, 4-dioxane-HCl solution. The transport ratio was high when the membrane potential difference was large and the high value was maintained for a long time in HCl-NaCl system. In addition, the transport ratio was also measured in the case where poly(styrenesulfonate) ion of large size was used as a cOunter ion and was compared with that in the case of PAC-PVSK system. IR measurement of sulface of memb rane dipped in acidic or alkaline solution revealed that the acetive and selective transport of alkali metal ions depended on the physical and chemical factors in the presence of OSO₃K free group in MC.

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Electron spin resonance (ESR) was applied for state analysis of nickel components contained in hopeite crystals formed on a zinc plated steel. The hopeite crystal, Zn₃(PO₄)₂.4H₂O, form ed in the zinc phosphate solution without Ni²⁺, was ESR inactive (Fig.2), due to the absence of transition metal ions with unpaired electron. On the contrary, another hopeite crystals formed in a zinc phosphate solution with Ni2+ exhibited an ESR signal (Fig.6). This shows that the Ni incorporated in the crystals exsists as an ion. The g values of Ni²⁺ in hopeite crystals and in reference compounds are given in Table 2. The g₁ and g₂ values corresponding to the main transition in Ni did not vary even on dilution of the crystals with KCl. In Ni₃(PO₄).7H₂O as a reference sample, the g₁ value was, but the g₂ value was not, same as that for hopeite crystals. It is concluded that the Ni component in the hop eite crystals, Zn__xNi_x(PO₄)₂.4H₂O, was produced by partial substitution of Zn²⁺ with Ni²⁺ according to the following mechanism.

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Some organic halogen compounds (halocarbons) are recognized or suspected to be mutagen and/or carcinogen. A sampling method which determines the average concentration levels of halocarbons for 1-2 weeks and their total exposure levels for a long period has been proposed. Halocarbons in air were adsorbed by a selected activated carbon and desorbed by hexane. Air was supplied to the carbon column at a constant low flow rate (50-400 mi/min) for a long time by a miniscale vacuum pump fitted with a capillary tube (Fig.1). The activated carbon which was made from coal and with particle size of 0.25-0.42 mm showed, good performance of adsorption and desorption. The amount of the carbon enough to adsorb the halocarbons almost completely was 5 g. The adsorbed halocarbons were eluted with hexane at a flow rate of 30-50 mi/h by a simple equipment (Fig.3). The desorption efficiencies were sufficiently high for all compounds (Table 4). The eluate was analyzed by a gas chromatograph equipped with electron capture detector. The average concentrations of the halocarbons for 1-2 weeks could be determined at many sites by the proposed sampling method, and th is method was expected to be useful to monitor, and evaluate air pollution with halocarbons.

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Alumina-supported copper (II) chloride was found to be very effective for the regioselective chlorination of phenol and alkylphenols. The chlorination of phenol with CuCl₂/Al₂O₃ at 50°C for 1 h in acetonitrile gave a 75% yield of a mixture of p- and o-chlorophenol with parafortho ratio of 22. Alkylphenols were also selectively chlorinated under similar co nditions to give the corresponding chloroalkylphenols in high yield. As the size of alkyl group becomes larger, the rate and the selectivity decrease.

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